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The first chiral cerium halide towards circularly-polarized luminescence in the UV region

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Science China Chemistry 2024年第6期67卷 1961-1968页

作者： Xinyi Niu Zhichao Zeng zhaoyu wang Haolin Lu Bing Sun Hao-Li Zhang Yongsheng Chen Yaping Du Guankui Long Tianjin Key Lab for Rare Earth Materials and Applications Renewable Energy Conversion and Storage CenterSmart Sensing Interdisciplinary Science CenterSchool of Materials Science and EngineeringNational Institute for Advanced MaterialsNankai UniversityTianjin300350China Tianjin Key Lab for Rare Earth Materials and Applications Center for Rare Earth and Inorganic Functional MaterialsHaihe Laboratory of Sustainable Chemical TransformationsSmart Sensing Interdisciplinary Science CenterSchool of Materials Science and EngineeringNational Institute for Advanced MaterialsNankai UniversityTianjin300350China State Key Laboratory of Applied Organic Chemistry Key Laboratory of Special Function Materials and Structure Design(Ministry of Education)College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000China The Centre of Nanoscale Science and Technology and State Key Laboratory of Elemento-Organic Chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin300071China

Chiral organic-inorganic hybrid metal halides(OIHMHs)have attracted broader scientific community recently in spin lightemitting diodes,and circularly polarized light-emitting ***,the emission peaks of the reported chiral OIHMHs mainly locate in the visible region,and chiral OIHMH with ultraviolet(UV)circularly polarized luminescence(CPL)has been rarely *** fill this gap,cerium,a unique rare-earth(RE)element with tunable luminescence from UV to the visible region owing to the 4 f-related electronic transition,was introduced to construct the first RE-based chiral OIHMHs,R/*** chirality is successfully transferred from the chiral organic cations to the inorganic cerium chloride framework in R/S-MCC,as confirmed by the single crystal structures,circular dichroism,and *** emission spectra of R/S-MCC are in the UV region,originating from the characteristic d-f transition of Ce^(3+),which making the Ce-based metal halides are ideal candidates towards CPL light sources in the UV ***,R-and S-MCC are the first RE-based OIHMHs,also the first chiral metalhalides with UV *** work opens a new avenue for the development of the chiral OIHMH family towards RE-based chiral *** RE-based chiral metal halides couple the unique and superior optical,electrical,magnetic,and spintronic properties of RE elements with chirality could accelerate the development of chiral optoelectronics and spintronics toward real applications.

关键词： chiral rare-earth halide ultraviolet circularly-polarized luminescence d-f transition rare-earth halide perovskite chiral perovskite

Lattice-mismatch-induced formation of defect-rich Pd–Cu alloy nanocages for enhanced formic acid oxidation activity

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Science China Chemistry 2024年

作者： Zhaojun Liu Zhengyan wang zhaoyu wang Hao Yuan Yuke Bai Xiaoxiao wang Zerui Mu Chunxia Wu Kai Liu Zhun Hu Chuanbo Gao Sate Key Laboratory of Multiphase Flow in Power Engineering Frontier Institute of Science and Technology Xi'an Jiaotong University Institute of Industrial Catalysis School of Chemical Engineering and Technology Xi'an Jiaotong University

Crystallographic defects in noble metal nanocrystals are recognized as highly active catalytic sites, significantly enhancing activities in many important reactions. Despite their importance, synthesizing noble metal nanocrystals with a high density of defects poses a considerable synthetic challenge. Here, we present a novel lattice mismatch-induced formation mechanism to create high-density defects in noble metal nanocrystals. This approach takes advantage of lattice mismatch to enable nonepitaxial nucleation and growth of a noble metal on a foreign metal substrate, forming abundant noble metal crystallites with random lattice orientations not dictated by the substrate lattice. As these crystallites grow extensively, they merge, forming numerous grain boundaries and yielding defect-rich noble metal nanocrystals. Defect-rich alloy nanocrystals can also be synthesized through a subsequent vacancy-diffusion alloying process. We take defective PdCu alloy nanocages as an example and demonstrate the effectiveness of crystallographic defects in enhancing catalytic performance of noble metal *** nanocages exhibit superior activity in the electrocatalytic formic acid oxidation reaction, which is 1.6 times greater than their defect-free counterparts. Our strategy offers a new avenue for creating defect-rich noble metal nanocrystals as highly efficient catalysts for a wide array of catalytic applications.

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论老年语言抚慰

语言战略研究 2024年第4期9卷 81-88页

作者：赫琳王炤宇武汉大学文学院/中国语情与社会发展研究中心湖北武汉430072

老年语言抚慰是通过使用语言文字及相关产品和话语手段,对60岁以上人群进行心理疏导和情绪抚慰,满足其情绪调节、知识获取和家庭社会参与等需求的语言服务。老年人、抚慰者和抚慰环境是老年语言抚慰的三大要素。应重视老年语言抚慰体系... 详细信息

老年语言抚慰是通过使用语言文字及相关产品和话语手段,对60岁以上人群进行心理疏导和情绪抚慰,满足其情绪调节、知识获取和家庭社会参与等需求的语言服务。老年人、抚慰者和抚慰环境是老年语言抚慰的三大要素。应重视老年语言抚慰体系建设。首先需要重视老年人群体内部差异,依据年龄、受教育程度和居住地等特征推知个体的语言抚慰需求;其次应着力培育多种类型的语言抚慰者,践行会话、阅读和叙事3种语言抚慰方式;最后还要营造适宜的语言抚慰环境,助力老年人群体内部及不同年龄群体间互联互通。开展老年语言抚慰,不但有利于老年人的生存发展,还能促进社会全体成员凝心聚力,积极面对人口老龄化带来的问题和挑战。

关键词：老年语言抚慰语言抚慰者语言抚慰方式语言抚慰环境语言抚慰需求

临床实践指南应用障碍与实施策略:一项基于理论框架的范围综述

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中国循证医学杂志 2024年第8期24卷 934-942页

作者：廖姣姣王照宇王卉陶立元詹思延北京大学第三医院临床流行病学研究中心北京100191 北京大学公共卫生学院北京100191 哈佛大学公共卫生学院美国马萨诸塞州02115

目的利用文献范围综述的方法,使用决定因素框架对指南实施过程中的重要障碍因素进行分类汇总,并探索既往干预研究的实施策略对指南依从性的影响。方法计算机检索PubMed、CINAHL、MEDLINE、Embase、Scopus、Cochrane Library、SinoMed、C... 详细信息

目的利用文献范围综述的方法,使用决定因素框架对指南实施过程中的重要障碍因素进行分类汇总,并探索既往干预研究的实施策略对指南依从性的影响。方法计算机检索PubMed、CINAHL、MEDLINE、Embase、Scopus、Cochrane Library、SinoMed、CNKI、WanFang Data和VIP数据库,搜集与临床实践指南的实施障碍及策略相关研究,检索时限均为2011年1月1日至2023年6月10日。由4人根据纳入和排除标准完成文献初筛和二次筛选,提取文献的基本特征、指南实施的影响因素、指南实施的策略,采用定性和定量的方法分析结果。结果本范围综述共纳入61篇文献。指南实施的影响因素可以分为指南自身、外部因素、内部因素、个人因素和实施过程5个类别,其中最常见的实施障碍为卫生专业人员的指南知识或技能不足(n=21,34.4%),医护认为使用指南的必要性不足(n=17,27.9%),医院自身因素不合理(n=16,26.2%)。而指南实施的促进因素有指南基于高质量研究证据(n=5,8.2%),良好的科室或医院文化(n=4,6.6%),指南知识和信息的可及性较高(n=4,6.6%),以及医生过硬的专业能力(n=4,6.6%)。指南实施策略的整体有效率为50%。临床决策支持系统可以提高指南的依从性,指南的教育和培训是最常用的方法之一,但对于提高指南依从性的效果不稳定。结论指南实施的主要障碍是医生实施指南的能力和需要不足、医院的结构欠佳和资源匮乏。但障碍因素并不绝对,建议使用实施策略来改善指南的吸收和实施,其中临床决策支持系统是促进指南依从性的有效措施。

关键词：范围综述临床实践指南依从性障碍实施策略

Mathematical Representation of WECC Composite Load Model

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Journal of Modern Power Systems and Clean Energy 2020年第5期8卷 1015-1023页

作者： Zixiao Ma zhaoyu wang Yishen wang Ruisheng Diao Di Shi Department of Electrical and Computer Engineering Iowa State UniversityAmesIA 50011USA GEIRI North America San JoseCA 95134USA

Composite load model of Western Electricity Coordinating Council(WECC)is a newly developed load model that has drawn great interest from the *** analyze its dynamic characteristics with both mathematical and engineering rigors,a detailed mathematical model is *** composite load model of WECC is available in commercial software as a module and its detailed block diagrams can be found in several public reports,there is no complete mathematical representation of the full model in *** paper addresses a challenging problem of deriving detailed mathematical representation of composite load model of WECC from its block *** particular,we have derived the mathematical representation of the new DERA *** developed mathematical model is verified using both MATLAB and PSS/E to show its effectiveness in representing composite load model of *** derived mathematical representation serves as an important foundation for parameter identification,order reduction and other dynamic analysis.

关键词： Composite load model dynamic load modeling mathematical model three-phase motor DER_A model

A Comparative Study of the Sensitivity of F_v/F_m to Phosphorus Limitation on Four Marine Algae

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Journal of Ocean University of China 2013年第1期12卷 77-84页

作者： QI Hongju wang Jiangtao wang zhaoyu Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China

We studied the effects of nitrogen （N） and phosphorus （P） supply on Fv/Fm （maximal quantum yield of photosystem Ⅱ） in the algae Chaetoceros debilis, Dicrateria inornata, Platymonas subcordiformis and Heterosigma akashiwo to determine the sensitivity of Fv/Fm to P-limitation of the four species. Obvious decrease of Fv/Fm value was monitored in periods of P-depletion, the decrease showing different magnitudes among algal species. A more clear decrease of Fv/Fm in Platymonas subcordiformis and Heterosigma akashiwo was observed, compared with that in Chaetoceros debilis and Dicrateria inornata. After the re-supply of P, the index Fv/Fm of the four species all recovered quickly in 24h. Cell division was maintained and chlorophyll content continued to increase until the end of the experiment in Platymonas subcordiformis and Heterosigma akashiwo, while in Chaetoceros debilis and Dicrateria inornata, the division stopped in the later period when the growth of organisms came into the stationary phase. The most obvious respond of chlorophyll content to P-additions was observed in Heterosigma akashiwo culture in 24 h. The sensitivity of Fv/Fm to nutrient limitations is different among algal species, and much should be done to improve the application of this index.

关键词： Chaetoceros debilis Dicrateria inornata Platymonas subcordiformis Heterosigma akashiwo P limitation P depletion Fv/Fm ratio

Responses of Maximum Photosystem II Photochemical Efficiency of Phytoplankton Communities to Nutrient Limitation in the Coastal Sea of Qingdao, China

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Journal of Ocean University of China 2014年第1期13卷 83-90页

作者： wang zhaoyu wang Jiangtao QI Hongju Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China

Nutrient enrichment experiments with nitrogen(N) and phosphorus(P) were conducted with samples from two stations in the coastal waters of Qingdao, China, during summer to identify limiting nutrients. In late July of 2009, low P concentrations and the maximum photochemical efficiency of photosystem II(Fv /Fm) in the initial samples together with Fv /Fm and chlorophyll a(Chl a) responses to P addition indicated P limitation at the two stations. In early August, low P levels still limited phytoplankton growth at station A. Fv /Fm and Chl a were the highest in the NP treatments at station B, suggesting an N/P co-limitation. In mid-September, nutrient concentrations and Fv /Fm were elevated and phytoplankton communities were healthy. Greater Fv /Fm and Chl a in the treatments with added P than those without the addition suggested potential P limitation at station A. Lack of Fv /Fm and Chl a responses following nutrient additions indicated N and P repletion at station B. At the end of July 2010, neither N nor P was limited at station B. Additionally, Fv /Fm coupled with 24-h-long nutrient enrichment experiments can be used to detect P limitation and N/P co-limitation to natural populations. This method can be more accurate for assessing co-limitation than the use of criteria of nutrient concentrations and ratios as indicators, and can provide more rapid results than nutrient addition bioassays using chlorophyll response as an indicator, when a population is potentially limited. Compared with the two conventional methods, the results based on Fv /Fm can also provide more detailed information about physiological states of the populations.

关键词： maximum photochemical efficiency of photosystem II(Fv /Fm) nutrient limitation nitrogen phosphorus phytoplankton

Transition-metal redox evolution and its effect on thermal stability of LiNixCoyMnzO_(2) based on synchrotron soft X-ray absorption spectroscopy

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Journal of Energy Chemistry 2021年第8期30卷 446-454,I0010页

作者： Chen Liang Wenhua Zhang Zesen Wei zhaoyu wang Qingsong wang Jinhua Sun State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China National Synchrontron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China

Based on the synchrotron soft X-ray absorption spectroscopy experiments,the fundamental electronic structures of layered Li NixCoyMnzO_(2)(NCM)are investigated systematically and the data of transitionmetal(TM)L-and O K-edges spectra are *** of Ni ions under different oxidation states is evaluated according to linear combination *** is found that the ratio of Ni^(4+)expands with the increase of Ni since it dominates in charge compensation during charging,and that the existence of Ni^(3+)is nearly negligible in delithiated *** valence state of Co also strongly depends on Ni content,the perceptible position shift of Co L_(3)-edge absorption peak towards higher energy in Ni-rich material agrees well with the small voltage plateau at around 4.2 *** stability of Mn is verified as no obvious spectral change with the Mn L-edge is ***,as Ni content rises,the O 2p holes near the Femi level increases with higher oxidation state of Ni,indicating the enhanced hybridization of O 2p-TM 3 *** NCMs with higher Ni content are prior to lose electron existing in highly hybridized Ni3 dO 2 p bands upon heating,which accounts for the pronounced O_(2)release in phase transitions and the deterioration in thermal *** detailed observation of the electronic structure evolution is one of the key ingredients to improving the electrochemical and thermal performance of NCM.

关键词： Lithium ion battery safety Cathode material Soft X-ray absorption spectroscopy Thermal stability

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海浪上下文信息补偿小目标检测算法

现代电子技术 2024年第17期47卷 98-104页

作者：李世宝李晨李作志王兆宇贾泽昆中国石油大学(华东)海洋与空间信息学院山东青岛266580 青岛港应急救援有限公司山东青岛266000

针对海上搜救图像中遇难人员在水面露出的面积小并且容易受到海浪反光、雨雾天气等恶劣环境影响,导致特征提取困难的问题,提出一种海浪上下文信息补偿小目标检测算法。首先,通过基于滑动窗口的图像预处理模块将图像进行裁剪,把关注点集... 详细信息

针对海上搜救图像中遇难人员在水面露出的面积小并且容易受到海浪反光、雨雾天气等恶劣环境影响,导致特征提取困难的问题,提出一种海浪上下文信息补偿小目标检测算法。首先,通过基于滑动窗口的图像预处理模块将图像进行裁剪,把关注点集中在目标物体周围,并减少图像中的无关区域,降低了计算量并提高了准确率;其次,提出一种海浪上下文模块,首次通过分析海浪的运动方向和强度,提取海浪上下文信息来辅助海上搜救小目标检测,提高检测精度。在SeaDronesSeev1和SeaDronesSeev2数据集上的实验结果表明,所提算法平均精度分别达到了73.29%和87.81%,相比YOLOv7-tiny算法,平均精度分别提高了21.84%和6.5%。所提算法提高了海上搜救小目标的检测精度,提高了海上搜救的效率。

关键词：卷积神经网络目标检测无人机海上搜救上下文信息 YOLOv7-tiny